Pipe-vise.



Patented Oct. 23' I900.

No. 660,367. T. DAVIS...

PIPE VISE.

(Appliution filed Feb. 27, 1900.)

(No Model.)

WITNESSES: INVENTOR: '14 Beams,

NIIED I STATES PATENT OFFICE.

THOMAS DAVIS, OF ORANGE, NEW JERSEY.

. PlPE -VISE.

SPECIFICATION formingpartof Letters Patent No. 660,367, dated October23, 1900.

Application filed February 27, 1900. Serial No- 6.671. (No model.)

To all whom it may concern.-

Be it known thatI, THOMAS DAVIS, a citizen of the United States,residing at Orange, in

the county of Essex and State of New Jersey,

have invented certain new'and useful Improvements in Pipe-Vises; and Ido hereby declare the following to be a full, clear, and

exact description of the inven tion,such as will I enable others skilledin the art to which it appertains to make and use the same, referencebeing had to the accompanying drawings, and

invention being to enable the vise to effec-f tually grip pipes or rodsof a greater range of variation of diameters, to secure a greaterstrength to resist the pressure on the bitingblades, and to secure otheradvantages and results, some of which may be referred to hereinafter inconnection with the description.

of the working parts.

The invention consists in the improved pipe-vise and in the arrangementsand combinations of parts of the same, all substantially as will behereinafter set forth and finally embraced in the clauses of the claim.

Referring to the accompanying drawings, in which like letters ofreference indicate corresponding parts in each of the several Views,Figure 1 is a side elevation of the improved pipevise. Fig. 2 is a planof the biting-blade, and Figs. 3, 4E, and 5 are side and end views ofthe same.

In said drawings, a indicates the frame of the vise, having a detachableyoke a at the top and inclined bearings a a toward the bottom.

I) b are the biting-blades, converging to ward their lower or bitingends and lying upon and parallel with the inclined bearings a of theframe.

c is a cross-head movable vertically on suitable guides or ways a of theframe and adapted to operate the blades 1), said blades being suspendedfrom the cross-head and adapted to slide thereon toward or apart fromeach other to maintain their parallel relation with the inclinedbearings, and d is a clampingsame as the screw is turned in onedirection or the other.

The features of construction thus described may in detail be of theconstruction shown and described in said prior patent, excepting theconstruction of the inclined bitingblades 1).

In the prior construction the biting-blades were effective in holdingthe pipe firmly against any tendency to turn when forming threads uponthe pipe or otherwise working thereon only when said pipes were of sizesbetween'certain very narrow limits of variation. When the pipe operatedon exceeded in diameter the said limits, then the vise failed toproperly grip and hold said pipe against the strain due to thethread-cutting tool, and consequently the value and adaptability of thevise for general shop purposes was greatly reduced.

By myimprovements the vise is largely increased in its scope ofoperations and brought within the limits of practicability. To this endthe blades 1) b are each provided with stepped biting ends, of which b bare the first step-bearings, adapted to grip pipes of small diameter,and b b are the second steps for engaging pipes of larger diameter. Thesteps are form ed by recessing, as at 12 one side portion of the end ofthe blade, thus forming the second edge 11 farther back on the blade.

As will be understood from an inspection of Fig. 1 of the drawings, thefirst step or end bearing 19 engages pipes which are of small diameterin comparison with the capacity of the vise, the second step-bearing bremaining unengaged, as shown. In the case of a large pipe the secondstep or recessed bearing edge b acts while the first remains idle.Evidently there will be an,intermediate size of such a diameter thatboth bearing edges will engage the surface of the pipe equally, and thusI may make a pipe-vise adapted particularly for certain specific sizesof pipe in which the pipe is engaged at two points on its periphery byeach biting-blade. This secures a diffusion of the strain and anenlarged contact with the pipe.

The biting-blades b are subjected under the pressure of the screw andcross-head to great strain, and should the inclined bearings of theframe be at all irregular or should extraneous matter be insertedbetween the blade and bearing, lifting said blade slightly from theinclined surface, there is a tendency to break the first step-bearing bby rupturing the hard and brittle steel. would this be true if therecess 5 back from the extreme biting edges, were formed right angularin cross-section. the first or extreme biting-bearing b, so that itresists the pressure by forming the recess 1) with curved walls, so thatsaid extreme step b gradually thickens as it approaches the secondbearing. This construction secures a maximum strength and avoidsfrequent breakage.

Having thus described the invention, what I claim as new is- 1. In apipe-vise, the combination with the frame having oppositely-inclinedbearings, of a pair of biting-blades arranged to slide on "said bearingsand maintain a parallel relation thereto, each blade having at its lowerend two or more biting edges, and means for raising and lowering saidblades, substantially as set forth.

2. In a pipe-Vise, the combination with a Especially I therefore bracetreme step increasing in thickness toward the body of the blade,substantially as set forth.

4. As an article of manufacture, the improved biting-blade forpipe-Vises having at one side edge of its end a longitudinal recess bhaving curved walls in cross-section and opening at both the side andend of the blade, said recess forming an extreme biting edge b, whosewalls thicken toward its base, and

(a second biting edge b substantially as set forth.

In testimony that I claim the foregoing I have hereunto set my hand this20th day of February, 1900.

THOMAS DAVIS.

Witnesses:

CHARLES H. PELL, O. B. PITNEY.

